Dy{sub 0.64}{l_brace}Dy{sub 5}[Fe{sub 2}C{sub 9}]{r_brace}: A complex carbide with a composite structure
- Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 0118 Dresden (Germany)
- Ivan Franko National University of Lviv, Kyrylo and Methody Street 6, 79005 Lviv (Ukraine)
- Laboratory of Crystallography BGI Building, University of Bayreuth, Universitaetsstrasse 30, D-95440 Bayreuth (Germany)
The ternary carbide Dy{sub 5.64}[Fe{sub 2}C{sub 9}] has been prepared by high temperature synthesis from the elements. The compound forms as a composite structure with two partial structures, {l_brace}Dy{sub 5}[Fe{sub 2}C{sub 9}]{r_brace} and {l_brace}Dy{sub 0.64}{r_brace} crystallizing in space groups Pnam and Pbam, respectively. The lattice parameters a=2934.63(9) pm and b=1263.63(5) pm for the two partial structures are identical, whereas the c lattice parameters for {l_brace}Dy{sub 5}[Fe{sub 2}C{sub 9}]{r_brace} (c{sub H}=504.14(3) pm) and {l_brace}Dy{sub 0.64}{r_brace} (c{sub G}=1056.01(5) pm) are different. This gives rise to a modulated structure in the (3+1)D superspace group Pnam(00g) with q=c{sub H}/c{sub G}=0.4775. The refinement converged to R(F) values below 0.055 for each partial structure using harmonic and Crenel functions. The compound is a bad metallic conductor and represents a new structure type composed of Dy{sup 3+} species embedded in a matrix of discrete planar FeC(C{sub 2}){sub 2} units and edge-sharing Fe(C{sub 2}){sub 4} tetrahedra forming infinite chains Fe(C{sub 2}){sub 4/2} running along the c axis. - Graphical abstract: Dy guest atoms (green) within an carbon octahedral channel of the modulated structure together with a tetrahedral Fe(C{sub 2}){sub 4/2} chain and triangular planar FeC(C{sub 2}){sub 2} groups in the crystal structure of Dy{sub 0.64}{l_brace}Dy{sub 5}[Fe{sub 2}C{sub 9}]{r_brace}. Highlights: Black-Right-Pointing-Pointer The first successful refinement of a large composite structure Dy{sub 0.64}{l_brace}Dy{sub 5}[Fe{sub 2}C{sub 9}]{r_brace}. Black-Right-Pointing-Pointer The presence of two kinds of complex anions with Fe as central atoms and C-ligands within this structure. Black-Right-Pointing-Pointer The oxidation state of the Fe atoms are low, they can be assigned Fe{sup I} and Fe{sup II}.
- OSTI ID:
- 22012127
- Journal Information:
- Journal of Solid State Chemistry, Vol. . 190; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
Similar Records
Ce{sub 2}AgYb{sub 5/3}Se{sub 6}, La{sub 2}CuErTe{sub 5}, and Ce{sub 2}CuTmTe{sub 5}: Three new quaternary interlanthanide chalcogenides
A series of 2D lanthanide (III) coordination polymers constructed from 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate